Objective To study the burden of shigellosis in Zhengding,Hebei province.Methods In 2002,a population and treatment center-based surveillance targeted to treate diarrhea was conducted in Zhengding.Stool sample was collected from each consented diarrhea cases for Shigetta.spp isolatiou.The incidence rates were calculated by age groups.To detect potential sequelae related to Shtgella infection,the confirmed shigellosis cases were followed-up in 90 days after presentation.Results In 2002,the incidence of diarrhea in catchment area was 133/1?000/year.The highest incidence rate(1?388/1?000/year)was found in infants;the incidence was 618/1?000/year in children under 5 years of age.Shigella.spp was isolated from 331 diarrhea patients.The incidence rate was 4.4/1?000/year.The highest incidence rate was found in children of 3 to 4 years of age.Followed with incidence in people elder than 60 years of age,which was 7/1000/yearo Feve-r and bloody stool were the most important clinical characteristics of shigellosis.No Shigella infection related sequelae or death were found during study period.Significant relationships were found between incidence of shigetlosis,average temperature and rainfall.Conclusion Compared with the noticeable infectious diseases report,tremendous disease burden of shigellosis was found in Zhengding.To control the epidemic of shigellosis,mass immunization targeted to children under 5 years old and people eider than 60 years old should be considered.

In order to understand the long-term efficacy of HB vaccine in susceptible poplulation immunized with a two-dose hepatitis B vaccine regimen(10ug/dose),132 HBV susceptible people of 0～70 years old were immunized with a two-dose hepatitis B vaccine by 0,3 month schedule in 1985 in Zhengding County of Hebei Province.Their serum samples were detected for HBsAg,anti-HBs and anti-HBc by SPRIA kits.All of the vaccinees displayed an anti-HBs titer of S/N≥2.1 6 months after immunization,84.8% of the vaccinees developed such a titer after 12 months(94.30% in 20 years old vaccinees and 74.20% in ≥20 vaccinees).The anti-HBs positive rate dropped to 59.31%(S/N≥2.1)or 18.6%(S/N≥10.0)at the 14 th year, no difference was found between two age groups.In the period of observation,one had become HBsAg positive but negatively serocenverted 3 months later. The two-dose hepatitis B vaccine regimen for the susceptible population gives good immune efficacy.

Objective To observe the effects of booster immunization of live attenuated hepatitis A vaccine given at different schedules and explore an optimal immune schedule.Methods The blood samples were collected from the children aged 1 7 years in Zhengding County,Hebei Province,and detected for anti HAV.A total of 3515 susceptible children were selected and divided into vaccination and blank control groups randomly,according to the months when they were born.The children in vaccination group were injected with one dose (primary immunization) of live attenuated HA vaccine,and the immune effects of them were observed.On the basis of this,a proportion of the children were randomly selected and given one booster at the 12 th month,or 2 boosters at the 2 nd and 6 th month after the primary immunization respectively.The antibody dynamics were observed 1,2,3,6,7,12,13 and 24 months after the primary immunization respectively.Results Both positive conversion rate(94.9%) and GMT(131.3mIU/ml) of HA antibody reached peak values 3 months after the primary immunization.However,they decreased to 79.8% and 79.6mIU/ml respectively 12 months after the primary immunization.After the boosters were given,antibody positive rate reached 100%,and antibody level increased doubly.The GMT of antibody induced by a booster given at the 12 th month after the primary immuniztion was the highest (3294.5mIU/ml).Conclusion Live attenuated HA vaccine showed good immunological memory and was suitable for vaccination at a schedule of 0,12 month.

In order to understand the anti-HBs persistence and the long-term preventive efficacy in newborns after vaccination with plasma-derived hepatitis B vaccine,a cohort observation was carried out in the following 1～14 years in Zhengding County,Hebei Province.The newborns were vaccinated with 10ug/ml×3 doses of hepatitis B vaccine,and 762 newborns who were HBsAg negative after primary immunization were selected for a cohort observation from 1986 to 1989.Their serum samples were detected qualitatively for hepatitis B infecting markers,including HBsAg,anti-HBs and anti-HBc by SPRIA Kits.The annual HBsAg positive seroconversion rate was counted by life-table method.The results showed that the anti-HBs positive rates were from 94.44% to 57.89% for babies born to HBsAg negative mothers and from 95.83% to 62.26% for babies born to HBsAg positive mothers at the 1 st to 9 th year,and still 50% or so at the 10 th to 14 th year.The person-year HBsAg positive seroconversion rate was 0.08%(6/7612.5),and none of the HBsAg positively converted children became HBsAg chronic carriers.Compared with the baseline(1.13%)before immunization,the protective rate was 92.92%.In conclusion,the protective efficacy of plasma-derived hepatitis B vaccine persisted at least 14 years,and a booster dose seems not necessary within at least 14 years after the primary three-doses immunization to newborns.

OBJECTIVE:To understand the protective efficacy of China-made recombinant hepatitis B vaccine expressed by transgenic Chinese hamster ovary cell line among newborns.METHODS:2 969 newborns in seven townships in Zhengding County, Hebei Province, were vaccinated with 10 microgram x 3 doses of China-made recombinant hepatitis B vaccine expressed by transgenic Chinese hamster ovary cell line according to the 0 - 1 - 6 month schedule from 1 January 1997 to 31 August 1999. The newborns were to be vaccinated with the first dose within 24 hours after they were born. 1906 serum samples were selected in April 2000 to detect the hepatitis B infection markers, including HBsAg, HBsAb and HbcAb by RIA kits.RESULTS:2 783 of the 2 969 newborns (93.74%) were vaccinated with three doses, 2 833 of them (95.42%) were vaccinated with the first dose within 24 hours after they were born. The anti-HBs positive rate was 98.25% (S/N >/= 2.1) or 94.26% (S/N >/= 10.0), and the geometric mean titer (GMT) value of antibody was 77.64 within the first year after the whole course vaccination. Then the antibody level decreased gradually with the lapse of time. The HBsAb positive rate was 92.31% (S/N >/= 2.1) or 68.96% (S/N >/= 10.0), and GMT value was 22.86 within the third year after vaccination. The HBsAg positive rates remained less than 1%, the HBcAb positive rates and HBV infection rates remained 1% approximately 3% within 3 years after vaccination.CONCLUSION:The protective efficacy of China-made recombinant hepatitis B vaccine is satisfactory.

观察了正定县吴兴乡新生儿实施乙型肝炎(乙肝)疫苗普种后14年的免疫学效果.该乡自1986年开始对所有新生儿结合农村计划免疫,按0、1、6个月程序接种3剂乙肝疫苗,在1986～1996年用血源乙肝疫苗,1997～1999年用重组(CHO细胞)乙肝疫苗.全程接种率1986～1996年为87.16%,1997～1999年为93.74%.于1999年普查采血,用固相放射免疫试剂检测乙肝病毒表面抗原(HBsAg)与抗体(抗-HBs)以及乙肝病毒核心抗体(抗-HBc),并与本地免疫前同龄儿童HBsAg阳性率进行比较,计算乙肝疫苗的免疫效果.结果显示:乙肝疫苗免疫后,1～14岁儿童保护性抗-HBs阳性率为94.74%～10.27%,S/N值几何平均滴度(GMT)为 76.72～5.62,随着免疫年限的延长而逐渐降低;HBsAg在10岁以前无升高趋势,1～14岁儿童的HBsAg总阳性率1.27%,与免疫前同龄儿童的10.5%相比,保护率为87.9%(95%可信限83.18%～93.38%).抗-HBc阳性率为2.26%,与免疫前同龄儿童的35.1%相比,降低了93.56%.新生儿乙肝疫苗免疫后随年龄的增长保护性抗体水平逐年下降,HBsAg阳性率10～14岁开始出现升高趋势,而在10岁以前未见升高趋势,说明免疫后10年间效果良好,无需加强免疫.

<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">目的　探索乙型肝炎 （乙肝 ）疫苗 2针法的免疫效果。方法　在河北正定县选择某乡 7个村为试验现场 ,进行了 14年观察。筛选 1～ 7岁HBV易感儿童 2 6 1名 ,按 0、3月免疫程序接种 2针 10 μg乙肝血源疫苗 ,全程免疫后 1、2、3、4、5、6、8、10和 14年对观察人群采集血清标本 ,检测HBsAg、抗 -HBs和抗 -HBc。 结果　抗 -HBs阳性率随免疫年限延长逐渐下降 ,由免疫后第 1年的 93 5 7%降为免疫后 14年的 5 2 13%,在观察期间 ,只检测到 1例HBsAg阳转者 ,并形成了慢性携带状态。结论　 2针免疫法与 3针免疫法的免疫效果无差别 ,在某些贫穷和交通不太方便的地区二针免疫法有推广价值。</span>

ObjectiveTo access the efficacy of China-made live attenuated hepatitis A vaccine (H 2 strain).Methods3 515 HAV susceptibles aged from 1～7 years old were randomized individually into vaccine and control group by birth month. Children in the vaccine group were given one dose of live attenuated hepatitis A vaccine while the children in the control group were given nothing. The attack rate in vaccine and control groups were followed up for 3.5 years after vaccination.ResultsIn the 3.5 years of following up, 14 hepatitis A cases were found in the control group and 1 case in control group. The attack rate in vaccine group and control group was 8.47 ‰ and 0.55 ‰ respectively. The difference of attack rate between the vaccine and control groups were significantly important and the efficacy of the vaccine was 93.51 %(95% lower confidence interval: 64.56 %).ConclusionThe efficacy of live attenuated hepatitis A vaccine (106.5TCID50/ml) was good and it can be used for mass immunization.

为了解婴儿按0、1、6个月程序接种3剂乙型肝炎(乙肝)疫苗后,对抗体应答低下者实施再免疫后的乙肝病毒表面抗体(抗-HBs)阳转状况,在正定县7个乡选取1997年1月1日～1998年8月31日出生的婴儿,按0、1、6个月程序实施3剂乙肝疫苗免疫,于1999年5月采血检测抗-HBs、乙肝病毒表面抗原(HBsAg)和乙肝病毒核心抗体(抗-HBc),对3项指标均阴性的90例又接种了1～2剂乙肝疫苗,2剂间隔1个月,分别在每剂接种1个月后采血检测抗-HBs.结果显示:再免疫1剂乙肝疫苗后1个月抗-HBs阳转率为85.6%(S/N≥2.1)和65.6%(S/N≥10.0).对再免疫1剂后仍无抗体应答者中的8例又接种了第2剂乙肝疫苗,经1个月检测抗-HBs全部阳转,其中4例抗体S/N值≥10.0;同时对再免疫1剂后抗-HBs弱阳性(S/N值2.1～9.9)者中的15例又接种了第2剂乙肝疫苗,经1个月后检测仅4例抗-HBs S/N值≥10.0,占26.7%.因此,对按3剂标准程序接种乙肝疫苗后免疫失败者再接种疫苗,可以诱导抗-HBs阳转.

"八五”期间,对国产H2株甲肝减毒活疫苗进行了大规模现场考核,由于现场所用疫苗滴度偏低(约为10 5.0-5.5TCID50),免疫后抗体阳性率仅为30%～40%,保护效果约为70%,结果不甚理想.为此我们对滴度在10 6.5TCID50以上的疫苗(规范化)再度进行了大规模现场考核.结果如下:

为探讨甲型肝炎(甲肝)减毒活疫苗(H2减毒株)0、12个月免疫程序的效果,并观察甲肝疫苗免疫儿童12个月加强免疫前后抗-HAV阳转率和几何平均浓度(GMC),在正定县选无肝病史、未注射过甲肝疫苗和免疫球蛋白、血清抗-HAV阴性的1～7岁易感儿童,接种甲肝减毒活疫苗,免疫后12个月和加强免疫后1个月采血,用微颗粒酶免疫测定法检测.结果显示:免疫后12个月阳转率为90.0%,GMC为141.2mIU/ml,加强免疫后1个月阳转率为100%,GMC上升到2747.1mIU/ml～3926.3mIU/ml,比加强免疫前平均升高23倍.表明H2株甲肝减毒活疫苗具有较好的免疫记忆反应.

为了探索国产甲型肝炎(甲肝)减毒活疫苗不同剂量、不同免疫程序的免疫效果,并与甲肝灭活疫苗进行比较,在河北省正定县某乡3个村筛选 3～13岁的甲肝易感儿童211名,按年龄分层随机分为甲肝减毒活疫苗A 组(0、6、12个月)、B组(0、6个月)和甲肝灭活疫苗C组(0、6 个月).这3个组按不同免疫程序减毒活疫苗或灭活疫苗免疫后1、6、7、 12、13、24个月采血,检测抗甲肝病毒抗体(抗-HAV).结果显示 :A、B、C 3个组在首剂疫苗免疫后1个月时抗-HAV阳转率均较低(3 3.87%～42.22%);第2剂疫苗免疫后1个月抗体水平均有大幅度提高,抗-HAV阳转率为97.67%～100.00%,几何平均滴度(GMT )为1?107.16mIU/ml～2?477.52mIU/ml,升高20 倍以上;首剂免疫后12个月抗-HAV阳性率均为100.00%,但GM T下降了64.9%～57.0%.仅A组首剂免疫后12个月时注射了第3 剂减毒活疫苗,1个月后抗体GMT呈5.7倍增长.首剂免疫后24个月时 ,3个组抗-HAV阳性率为92.98%～98.11%,GMT为213. 87～642.69mIU/ml.低滴度减毒活疫苗基础免疫后再免疫能诱导很好的免疫回忆反应.

<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">为了解新生儿乙肝疫苗免疫后抗－ＨＢｓ持久性及远期保护效果，从１９８６年开始，结合农村计划免疫给新生儿接种３针１０μｇ／ｍｌ血源乙肝疫苗，对免疫后首次检测ＨＢｓＡｇ阴性的７６２名免疫儿童进行了最长１０年的追踪观察。结果（１）母亲ＨＢｓＡｇ阴性儿和阳性儿的抗－ＨＢｓ阳性率以Ｓ／Ｎ值≥２．１标准计算，分别从免疫后第１年９４．４４％和８４．２１％降至第１０年５０．２４％和３４．７８％，均呈逐年下降趋势；抗－ＨＢｓＳ／Ｎ值的ＧＭＴ由第２年的３１．６２和２３．９９降至第１０年的３．０９和２．５１，下降更为明显，且ＧＭＴ以免疫后３～５年下降最快，而抗－ＨＢｓ阳性率则以９～１０年下降最快。（２）母亲ＨＢｓＡｇ阴性儿６８８名，共观察了３５５９．０人年，出现５例ＨＢｓＡｇ阳转者，ＨＢｓＡｇ年阳转率０．１４％；母亲ＨＢｓＡｇ阳性儿７４名，共观察了４５６．５人年，出现１例ＨＢｓＡｇ阳转者，ＨＢｓＡｇ年阳转率０．２２％，出现的６例ＨＢｓＡｇ阳转者均未形成慢性携带状态。与乙肝疫苗免疫前同龄ＨＢＶ易感儿童ＨＢｓＡｇ年阳转率４．２７％相比，乙肝疫苗对母亲ＨＢｓＡｇ阴性儿和阳性儿的ＨＢｓＡｇ阳转保护率分别为９６．７２％和９４．８５％。</span>